Publications by authors named "Kawamura F"

Article Synopsis
  • * Researchers found that a specific gene responsible for encoding tRNA-specific adenosine deaminase is not essential for bacterial survival, and that tRNA can effectively decode various codons without it.
  • * The absence of inosine led to frameshifting during translation and affected bacterial growth, highlighting that inosine modifications are crucial for maintaining translational accuracy and growth regulation.
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Purpose: This report presents the adaptation of an assistive device chair for bedside sitting and its application in two patients with trunk control impairment in the acute stroke phase.

Materials And Methods: The device was built with polyvinylchloride (PVC) pipes and designed by a team of mechanical engineers and physiotherapists to maintain a prolonged sitting position with less demand from therapists. To test the device, two patients were followed up during the acute phase of stroke.

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This paper presents the first case of the successful eradication of a Coleoptera pest species over a wide area using a combination of male annihilation technique (MAT) and sterile insect technique (SIT) application. The sweet potato weevil, Cylas formicarius, is one of the most destructive and widely distributed pests of sweet potato, Ipomoea batatas. A project to eradicate it was launched in 1994 on Kume Island, Okinawa Prefecture, Japan.

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We clarified that the bandgap of inorganic materials is strongly correlated with their effective coordination number (ECoN) via first-principles calculations and experimental confirmations. Tin mono-sulphide (Pnma) and germanium mono-sulphide (Pnma) were selected as model cases since these materials successively alter the ECoN as the cell volume changes and show an uncommon relationship between cell volume and bandgap. Contrary to the common semiconductors, the bandgaps of SnS (Pnma) and GeS (Pnma) have a positive relationship with respect to cell volume.

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Ribosomal protein S14 can be classified into three types. The first, the C+ type has a Zn binding motif and is ancestral. The second and third are the C- short and C- long types, neither of which contain a Zn binding motif and which are ca.

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A novel ternary nitride semiconductor, CaSnN, with a layered rock-salt-type structure (3̅) was synthesized via a high-pressure metathesis reaction. The properties and structures of II-Sn-N (II = Ca, Mg, Zn) semiconductors were also systematically studied, and the differences among them were revealed by comparison. These semiconductor materials showed a rock-salt- or wurtzite-type structure depending on the combined effect of the synthetic conditions and the characteristics of the group II elements.

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Cytochrome P450 enzymes (CYP) function in drug metabolism in the liver. To evaluate numerous drug candidates, a high-content screening (HCS) system with hepatocyte-like cells (HLCs) that can replace adult human hepatocytes is required. Human hepatocellular carcinoma HepaRG is the only cell line capable of providing HLCs with high CYP3A4 expression comparable to that in adult hepatocytes after cell differentiation.

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The fields of drug discovery and regenerative medicine require large numbers of adult human primary hepatocytes. For this purpose, it is desirable to use hepatocyte-like cells (HLCs) differentiated from human pluripotent stem cells (PSCs). Premature hepatoblast-like cells (HB-LCs) differentiated from PSCs provide an intermediate source and steady supply of newly mature HLCs.

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Chromosomal translocation is a key process in the oncogenic transformation of somatic cells. Previously, artificial induction of chromosomal translocation was performed using homologous recombination-mediated loxP labeling of target regions followed by Cre-mediated recombination. Recent progress in genome editing techniques has facilitated the easier induction of artificial translocation by cutting two targeted genome sequences from different chromosomes.

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The ε subunit of F F -ATPase/synthase (F F ) plays a crucial role in regulating F F activity. To understand the physiological significance of the ε subunit-mediated regulation of F F in Bacillus subtilis, we constructed and characterized a mutant harboring a deletion in the C-terminal regulatory domain of the ε subunit (ε ). Analyses using inverted membrane vesicles revealed that the ε mutation decreased ATPase activity and the ATP-dependent H -pumping activity of F F .

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Individually, the ribosomal proteins L1, L23, L36, and S6 are not essential for cell proliferation of , but the absence of any one of these ribosomal proteins causes a defect in the formation of the 70S ribosomes and a reduced growth rate. In mutant strains individually lacking these ribosomal proteins, the cellular Mg content was significantly reduced. The deletion of YhdP, an exporter of Mg, and overexpression of MgtE, the main importer of Mg, increased the cellular Mg content and restored the formation of 70S ribosomes in these mutants.

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Pseudo III-V nitride ZnSnN is an earth-abundant semiconductor with a high optical absorption coefficient in the solar spectrum. Its bandgap can be tuned by controlling the cation sublattice disorder. Thus, it is a potential candidate for photovoltaic absorber materials.

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Research into inexpensive ammonia synthesis has increased recently because ammonia can be used as a hydrogen carrier or as a next generation fuel which does not emit CO. Furthermore, improving the efficiency of ammonia synthesis is necessary, because current synthesis methods emit significant amounts of CO. To achieve these goals, catalysts that can effectively reduce the synthesis temperature and pressure, relative to those required in the Haber-Bosch process, are required.

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B cell derived induced pluripotent stem cells (BiPSCs) were recently established from peripheral blood B cells by the simultaneous transfection of Yamanaka factors (Oct3/4, Sox2, Klf4, c-Myc) and C/EBPα using a Sendai virus vector. Here, using a different method, we established BiPSCs with immunoglobulin heavy chain (IgH) gene rearrangement from normal B cells purified from lymph nodes. The critical points of our method are pre-stimulation of B cells with IL-21 and CD40-ligand (CD40L), followed by consecutive transfection of highly concentrated Yamanaka factors using a retroviral vector.

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Background: Approximately 20% to 40% of patients with gastroesophageal reflux disease (GERD) are refractory to standard-dose proton-pump inhibitor (PPI) treatment.

Objective: We compared the efficacy and quality-of-life effects of 20 mg once daily (QD) versus 10 mg twice daily (BID) rabeprazole (RPZ) in patients with refractory GERD-related symptoms and sleep disturbances.

Methods: This multicenter, prospective, randomized, open-label study included patients in whom PPI treatment >4 weeks was ineffective.

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We recently reported an increase in dicentric chromosome (DIC) formation after a single computed tomography (CT) scan (5.78-60.27 mSv: mean 24.

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Article Synopsis
  • Ribosome dimers, inactive ribosome forms, were found in Bacillus subtilis during the early stationary phase and remained until regrowth started.
  • The formation of these dimers was dependent on the hpf gene, which promotes ribosome hibernation, and was expressed throughout the stationary phase.
  • While lacking ribosome dimers did not affect the viability of cells during the stationary phase, Δhpf mutant cells showed slower regrowth due to delayed restoration of their translational activity.
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The genome of Bacillus subtilis strain 168 encodes ten rRNA (rrn) operons. We previously reported that strains with only a single rrn operon had a decreased growth and sporulation frequency. We report here the isolation and characterization of suppressor mutants from seven strains that each have a single rrn operon (rrnO, A, J, I, E, D or B).

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To elucidate the biological functions of the ribosomal protein L34, which is encoded by the rpmH gene, the rpmH deletion mutant of Bacillus subtilis and two suppressor mutants were characterized. Although the ΔrpmH mutant exhibited a severe slow-growth phenotype, additional mutations in the yhdP or mgtE gene restored the growth rate of the ΔrpmH strain. Either the disruption of yhdP, which is thought to be involved in the efflux of Mg(2+), or overexpression of mgtE, which plays a major role in the import of Mg(2+), could suppress defects in both the formation of the 70S ribosome and growth caused by the absence of L34.

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Bacillus subtilis can acquire a higher tolerance to tetracycline by increasing the gene dosage of its resistance gene tetB. In this study, we estimated the multiplication effect of tetB on tetracycline tolerance. Cells harbouring multiple copies of tetB were found to comprise approximately 30 % of the total tetracycline-resistant cell population when selected on medium containing 10 µg tetracycline ml(-1).

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Human adult hepatocytes expressing CYP3A4, a major cytochrome P450 enzyme, are required for cell-based assays to evaluate the potential risk of drug-drug interactions caused by transcriptional induction of P450 enzymes in early-phase drug discovery and development. However, CYP3A7 is preferentially expressed in premature hepatoblasts and major hepatic carcinoma cell lines. The human hepatocellular carcinoma cell line HepaRG possesses a high self-renewal capacity and can differentiate into hepatic cells similar to human adult hepatocytes in vitro.

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Bacillus subtilis differentiates into various cellular states in response to environmental changes. It exists in two states during the exponential growth phase: motile cells and connected chains of sessile cells. Here, we identified new regulators of cell motility and chaining, the ribosomal proteins S21 (rpsU) and S11 (rpsK).

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The impacts of plasmid carriage on the host cell were comprehensively analysed using the conjugative plasmid pCAR1 in three different Pseudomonas hosts, P. putida KT2440, P. aeruginosa PAO1 and P.

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Article Synopsis
  • * The mutation leads to a decrease in levels of L2 and L16 proteins in ribosomes, suggesting that native L2 is necessary for proper assembly of L16 into the 50S ribosomal subunit.
  • * A separate suppressor mutation was found that, by increasing the expression of the yaaA gene, helps restore growth and sporulation by improving the assembly of the faulty L2 protein into functional ribosomes.
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Article Synopsis
  • The study investigated how varying numbers of rRNA (rrn) operons in Bacillus subtilis affect its growth and behavior, using eight mutant strains with 2 to 9 copies of the rrn operon.
  • Findings revealed that reducing rRNA copies from ten to one increased doubling time and decreased sporulation and motility, while normal sporulation required more than four copies.
  • Additionally, constructing 21 strains with two rrn operon copies showed varying growth rates and sporulation frequencies, highlighting the significant impact of rrn operon copy number on bacterial cellular functions.
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